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tsmux: Fix 0x81 descriptor for AC3 streams

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According to ATSCA/52:2018

https://prdatsc.wpenginepowered.com/wp-content/uploads/2021/04/A52-2018.pdf

Used wireshark as ground truth for detection/parsing.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/4681>
This commit is contained in:
Vivia Nikolaidou 2023-05-19 16:18:08 +03:00 committed by Edward Hervey
parent 7eca75130d
commit 7a98a4214b
1 changed files with 89 additions and 74 deletions
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163
subprojects/gst-plugins-bad/gst/mpegtsmux/tsmux/tsmuxstream.c
View file

@ -856,8 +856,52 @@ tsmux_stream_default_get_es_descrs (TsMuxStream * stream,
break;
case TSMUX_ST_PS_AUDIO_AC3:
{
guint8 add_info[6];
guint8 add_info[10];
guint8 *pos;
guint bitrate;
gboolean has_language;
guint total_length = 7;
guint bitrates[20][2] = {
{32000, 0x00}
,
{40000, 0x01}
,
{48000, 0x02}
,
{56000, 0x03}
,
{64000, 0x04}
,
{80000, 0x05}
,
{96000, 0x06}
,
{112000, 0x07}
,
{128000, 0x08}
,
{160000, 0x09}
,
{192000, 0x0A}
,
{224000, 0x0B}
,
{256000, 0x0C}
,
{320000, 0x0D}
,
{384000, 0x0E}
,
{448000, 0x0F}
,
{512000, 0x10}
,
{576000, 0x11}
,
{640000, 0x12}
};
gint i;
guint bitrate_code = 0x12;
pos = add_info;
@ -873,10 +917,18 @@ tsmux_stream_default_get_es_descrs (TsMuxStream * stream,
* num_channels 4 bslbf
* full_svc 1 bslbf
* langcod 8 bslbf
* [...]
* mainid 3 uimsbf
* priority 2 bslbf
* reserved 3 '111'
* textlen 7 uimsbf
* text_code 1 bslbf
* text 8*textlen bslbf
* language_flag 1 bslbf
* language_flag_2 1 bslbf
* reserved 6 '111111'
* language if flag 3*8 uimbsf
* language_2 if flag_2 3*8 uimsbf
*/
*pos++ = 0x81;
*pos++ = 0x04;
/* 3 bits sample_rate_code, 5 bits hardcoded bsid (default ver 8) */
switch (stream->audio_sampling) {
@ -895,103 +947,66 @@ tsmux_stream_default_get_es_descrs (TsMuxStream * stream,
}
/* 1 bit bit_rate_limit, 5 bits bit_rate_code, 2 bits suround_mode */
switch (stream->audio_bitrate) {
case 32:
*pos++ = 0x00 << 2;
bitrate = MAX (stream->audio_bitrate, stream->max_bitrate);
for (i = 0; i < G_N_ELEMENTS (bitrates); i++) {
if (bitrate < bitrates[i][0]) {
break;
case 40:
*pos++ = 0x01 << 2;
break;
case 48:
*pos++ = 0x02 << 2;
break;
case 56:
*pos++ = 0x03 << 2;
break;
case 64:
*pos++ = 0x04 << 2;
break;
case 80:
*pos++ = 0x05 << 2;
break;
case 96:
*pos++ = 0x06 << 2;
break;
case 112:
*pos++ = 0x07 << 2;
break;
case 128:
*pos++ = 0x08 << 2;
break;
case 160:
*pos++ = 0x09 << 2;
break;
case 192:
*pos++ = 0x0A << 2;
break;
case 224:
*pos++ = 0x0B << 2;
break;
case 256:
*pos++ = 0x0C << 2;
break;
case 320:
*pos++ = 0x0D << 2;
break;
case 384:
*pos++ = 0x0E << 2;
break;
case 448:
*pos++ = 0x0F << 2;
break;
case 512:
*pos++ = 0x10 << 2;
break;
case 576:
*pos++ = 0x11 << 2;
break;
case 640:
*pos++ = 0x12 << 2;
break;
default:
*pos++ = 0x32 << 2;
break; /* 640 Kb/s upper limit */
}
bitrate_code = bitrates[i][1];
}
*pos = bitrate_code << 2;
*pos++ |= 0x80; /* This is a maximum bitrate */
/* 3 bits bsmod, 4 bits num_channels, 1 bit full_svc */
switch (stream->audio_channels) {
case 1:
*pos++ = 0x01 << 1;
*pos = 0x01 << 1;
break; /* 1/0 */
case 2:
*pos++ = 0x02 << 1;
*pos = 0x02 << 1;
break; /* 2/0 */
case 3:
*pos++ = 0x0A << 1;
*pos = 0x0A << 1;
break; /* <= 3 */
case 4:
*pos++ = 0x0B << 1;
*pos = 0x0B << 1;
break; /* <= 4 */
case 5:
*pos++ = 0x0C << 1;
*pos = 0x0C << 1;
break; /* <= 5 */
case 6:
default:
*pos++ = 0x0D << 1;
*pos = 0x0D << 1;
break; /* <= 6 */
}
*pos++ |= 0x01; /* full_svc is hardcoded to 1 for now */
/* deprecated langcod */
*pos++ = 0xff;
/* 3 bits mainid, 2 bits priority, 3 bits reserved */
*pos++ = 0x0f;
/* 7 bits textlen, 1 bit text_code */
*pos++ = 0x00;
/* no text provided, jumping directly to language */
descriptor = gst_mpegts_descriptor_from_registration ("AC-3",
add_info, 6);
has_language = (stream->language[0] != '\0');
if (has_language) {
*pos++ = 0xbf;
*pos++ = stream->language[0];
*pos++ = stream->language[1];
*pos++ = stream->language[2];
total_length = 10;
} else {
*pos++ = 0x3f;
}
descriptor = gst_mpegts_descriptor_from_registration ("AC-3", NULL, 0);
g_ptr_array_add (pmt_stream->descriptors, descriptor);
descriptor =
gst_mpegts_descriptor_from_custom (GST_MTS_DESC_AC3_AUDIO_STREAM,
add_info, 6);
add_info, total_length);
g_ptr_array_add (pmt_stream->descriptors, descriptor);
break;
}
case TSMUX_ST_PS_AUDIO_DTS: